Canon News has uncovered a patent that shows Canon is working on small RF prime lenses, like non-L.
Japan patent 2019-152683 does include the RF 35mm f/1.8 IS STM Macro in one of the embodiments, but keep in mind that lens design can sometimes build off of existing lenses.
RF prime lens optical formulas in this patent:
Canon RF 20mm f/2 (Lens length of 70mm)
Canon RF 35mm f/2.8 (Lens length of 40mm)
Canon RF 45mm f/2.8 (Lens length of 43mm)
Canon RF 35mm f/2 (Lens length of 30mm)
Beyond the prime lenses, there is also a wide-angle f/4 zoom included.
Canon RF 16-35mm f/4 (Lens length 90mm – 97mm)
Looking at all the embodiments, I think only the RF 16-35mm f/4 could realistically be coming.